1. Field of the Invention
This invention relates generally to apparatus for detecting faults in electrical transmission and/or distribution apparatus, and more specifically, to apparatus for detecting gap-type defects in electrical power line equipment in response to broadband radio frequency noise generated thereby.
2. Description of the Prior Art
Radio frequency noise has many causes. Of special interest to electric utilities is noise caused by arcing of charge across small gaps in transmission and distribution power line equipment. These gaps may develop over time due to expansion and contraction around metal hardware, the build-up of corrosion around metal hardware, or occasionally, improper installation. Arcing occurs when charge builds up on one side of the gap and discharges across the gap, most frequently near the peaks of the sinusoidal power curve. A multiplicity of discharges occur near each peak of the power curve. Each discharge generate broadband electrical noise which may cause interference to communication systems.
One method to detect such gaps defects is to locate and analyze the electrical noise generated thereby. The analysis must differentiate between gap-type noise and noise due to other sources, such as ignition noise, atmospheric noise, and corona noise.
The analysis may require the displaying of signals received by a radio receiver on an oscilloscope. Such analysis requires trained personnel to recognize the pattern of noise generated by gap-type defects and AC power line equipment.